Cylinder honing tool



1962 J. T. CLARK CYLINDER HONING TOOL Filed Aug. 10, 1961 INVENTOR.JAMES T. CLARK ATTORNEY 3,065,579 CYLINDER HONING T001.

James T. Clark, Fort Morgan, Colo., assignor to Clark- FeatherManufacturing (10., Fort Morgan, Colo, a corporation of Colorado FiledAug. 10, 1961, Ser. No. 131,969 3 Claims. ((11. 51-1842) This inventionrelates to a rotary cylinder honing tool for deglazing and resurfacingthe wall of an internal combustion engine cylinder.

The principal object of the invention is to provide an easily handled,rapid and efiicient cylinder honing tool for use in a conventionalelectric drill which will be selfcentering and self-bottoming and whichcan be quickly slipped into a cylinder of any size and which willautomatically, resiliently and uniformly expand to accurately maintainhoning elements against the wall of the selected cylinder regardless ofthe internal diameter of the latter.

While the improved cylinder honing tool will automatically expand toaccommodate a wide range of cylinder diameters, for instance a standardmodel thereof accommodates cylinders from 2" to 7" in diameter, it hasbeen found that in the usual shop, working on the smaller cylinders ofthe popular brands of automobile engines, it is inconvenient to berequired to constantly contract the tool from its large maximum capacityfor insertion into the smaller diameter cylinders being conventionallyworked upon. Therefore, another object of this invention is to provide,in a honing tool of a large diameter capacity, means for limiting theexpansion thereof to a diameter convenient for use upon the particularcylinders upon which the shop is working thus making it unnecessary toconstantly contract the hone from its full capacity for insertion intothe smaller diameter cylinders.

Other objects and advantages reside in the detail construction of theinvention, which is designed for simplicity, economy, and efiiciency.These will become more apparent from the following description.

In the following detailed description of the invention, reference is hadto the accompanying drawing which forms a part hereof. Like numeralsrefer to like parts in all views of the drawing and throughout thedescription.

'In the drawing:

FIG. 1 is a perspective view of the improved cylinder honing tool as itwould appear when being inserted into the upper extremity of aconventional automotive cylinder liner as indicated at 10;

FIG. 2 is a fragmentary vertical section taken on the line 22, in FIG.3; and

FIG. 3 is a cross section looking downwardly on the line 33, FIG. 2.

The cylinder honing tool of this invention employs a vertical pivotshaft portion 11 driven through the medium of a flexible shaft portion12 from a drive shaft portion 13 arranged to be inserted in the chuck ofa conventional electric drill. The drive shaft portion 13 is connectedto the flexible shaft portion 12 in any suitable manner, such as bymeans of a coupling sleeve 14, and the flexible shaft portion 12 isfixedly mounted in a receiving socket 15 in the upper extremity of thepivot shaft portion 11.

The drive shaft portion 13 is threaded, as indicated at 16, to receive aspring-compression-adjusting nut 17 which acts to compress a spring 18against a yoke 19 which is slidably mounted on the pivot shaft portion11.

The pivot shaft portion 11 is also threaded, as indicated at 20, toreceive a maximum-diameter pro-setting nut 21 and the lower extremity ofthe pivot shaft portion 11 is reduced in diameter and threaded to form aterminal stud 22 upon which an arm spreader 23 is fixedly mounted bymeans of a suitable clamp nut 24.

. Patented Nov. 27, 1962 The yoke 19 is formed with three hinge bosses25 projecting radially at spacing. Each hinge boss is drilled to receivea hinge rivet 26 upon which the upper extremity of a hone arm 27 ishingedly mounted.

The three hone arms 27 are channel-shaped in cross section and each isconvoluted longitudinally to form an outwardly and downwardly inclinedupper portion 28, an inwardly and downwardly inclined medial portion 29and a downwardly extending lower terminal portion 30 upon the lowerextremity of which a foot member 31 is tiltably mounted by means of apivot rivet 32.

The foot members 31 carry elongated honing pads 33 adhesively mounted ontheir outer faces. The pads may be rectangular abrasive stones or may beof felt or similar material. Preferably, one of the foot members 31 willcarry a felt pad and the remaining two foot members will carry abrasivestone pads.

The sides of the channels forming the upper arm portions 28 are turnedinwardly to form opposed retaining flanges 34. The arm spreader 23 isshaped to form three spokes 35 the extremities of which extend into thechannels of the upper arm portions 28. The sides of the spokes 35 arenotched, as shown at 36, to receive the inturned retaining flanges 34,as shown in FIG. 3.

In use, hone arms are squeezed together in the hand until the footmembers 31 can be inserted into the upper extremity of a cylinder orcylinder liner. The tool is then forced downwardly so that the hone pads33 ride fiat against the cylinder wall. When the hone arms arecompressed together the flanges 34 of their upper portions 28 slideupwardly in the spoke notches 36 forcing the yoke 19 upwardly againstthe bias of the compression spring.

When the hone arms are released, the expansion of the spring 18 forcesthe yoke downwardly causing the flanges 34 to ride downwardly andoutwardly in their spoke notches 36 to press the pads 33 outwardlyagainst the cylinder walls while the tool is rotated by the electricdrill motor. Since the shaft portions 11, 12 and 13 are flexible anyinaccuracies in incline or tilt of the drill motor are automaticallyaccommodated. If cylinders of smaller diameter than the maximum capacityof the tool are being constantly worked upon, the repeated squeezing orcontraction of the hone arms to the smaller cylinder diameter becomes atedious, time-consuming task.

The latter task is avoided by the use of the maximum diameterpro-setting nut 21. The latter nut acts to stop the descent of the yoke19, and the expansion of the hone arms 2?, at any desired point. Forinstance, if relative cylinders are being honed, the nut 21 is threadedupwardly on the pivot shaft portion 11 until the maximum expansionof'the hone arms is just suflicient to position the foot member rivetson a radius slightly less than the radius of the cylinder, as shown inFIG. 1. The nut 21 is then fixed in position in any desired manner suchas by means of a suitable set screw 37. After the latter setting hasbeen made, the tool can be quickly forced into the smaller cylinderswithout the preliminary squeezing.

While a specific form of the improvement has been described andillustrated herein, it is to be understood that the same may be variedWithin the scope of the appended claims, without departing from thespirit of the invention.

Having thus described the invention what is claimed and desired to besecured by Letters Patent is:

1. A cylinder honing tool comprising: a vertical shaft; an arm spreadermounted on the lower extremity of said shaft; a yoke slidably mounted onsaid shaft above said spreader; hone arms hinged to and depending fromsaid yoke in contact with said spreader; foot members pivotally mountedon the lower extremities of said hone arms; abrasive means carried bysaid foot members; a compression spring acting to urge said yokedownwardly to cause said hone arms to swing outwardly in consequence oftheir contact with said spreader; and adjustable stop means for stoppingthe downward travel of said yoke at any desired point, said stop meanscomprising a nut threaded on said shaft between said spreader and saidyoke and positioned to be contacted by the yoke as the latter descendsunder the influence of said spring.

2. A cylinder honing tool as described in claim I having means forfixedly locking said nut at any desired position on said shaft.

3. A cylinder honing tool comprising: a vertical shaft; an arm spreadermounted on the lower extremity of said shaft; a yoke slidably mounted onsaid shaft above said spreader; hone arms hinged to and depending fromsaid yoke in contact with said spreader; foot members pivotally mountedon the lower extremities of said hone arms; abrasive means carried bysaid foot members; a compresward movement of the latter at any desiredpoint.

References Cited in the file of this patent UNITED STATES PATENTS1,567,417 Campbell Dec. 29, 1925 2,560,727 Keiser July 17, 19512,736,146 Brooks Feb. 28, 1956 2,778,168 Clark Jan. 22, 1957 2,782,572Clark Feb. 26, 1957 3,005,294 Kushmuk Oct. 24, 1961

